Gemcraft

I have played this game for months can not get past level 12. Some where I had a note that said something about CTRL and creating gems, there was something else on the page but my eyes could not focus on it, and I can't find it again. Also i can't get above 4 on constructing gems. any help would be appreciated. I'm headed for board and care facility and I'd love to make a level 7 gem but maybe my hands just can't move fast enough any more. Thank you for your taking time to read this!
Rosie